Stage 17: backend defect fixes (nudge code, TG name, robot names/timing, multi-device push, move-duration metric + admin analytics)

- #3 nudge-on-own-turn: distinct result code nudge_own_turn + i18n (was reused 'not_your_turn')
- #2 sanitize connector registration name to the editable format; Player/Игрок-XXXXX fallback
- #5 variant-aware robot name pools (composed full/colloquial first + surname forms; ru gets <=20% latin)
- #4 move-number-aware robot move timing (early 1-5min -> late 10-90min, skew k=4)
- #7 emit move event to the actor too (multi-device sync); opponent_moved stays in-app only
- #1 live game_move_duration{variant,phase} histogram + admin console per-user min/avg/max columns and an inline-SVG move-time-by-move-number chart (offline from the journal)
- ProvisionRobot bypasses editor name validation (system names like 'Peter J.')

backend/internal/account/account.go

@@ -12,7 +12,6 @@ import (
 	"fmt"
 	"strings"
 	"time"
-	"unicode/utf8"
 
 	"github.com/go-jet/jet/v2/postgres"
 	"github.com/go-jet/jet/v2/qrm"
@@ -112,10 +111,41 @@ func (s *Store) ProvisionByIdentity(ctx context.Context, kind, externalID string
 	return s.provision(ctx, kind, externalID, provisionSeed{})
 }
 
+// ProvisionRobot provisions (or finds) the durable account backing a robot pool
+// member: a KindRobot identity carrying displayName, with chat and friend requests
+// blocked so the robot never engages socially. Robot names are system-generated, not
+// player-edited, so they bypass the editable display-name validation and may carry
+// forms the editor rejects (an abbreviated surname like "Peter J."). It is idempotent:
+// repeated calls converge the display name and both block flags.
+func (s *Store) ProvisionRobot(ctx context.Context, externalID, displayName string) (Account, error) {
+	acc, err := s.provision(ctx, KindRobot, externalID, provisionSeed{displayName: displayName})
+	if err != nil {
+		return Account{}, err
+	}
+	if acc.DisplayName == displayName && acc.BlockChat && acc.BlockFriendRequests {
+		return acc, nil
+	}
+	stmt := table.Accounts.UPDATE(
+		table.Accounts.DisplayName, table.Accounts.BlockChat,
+		table.Accounts.BlockFriendRequests, table.Accounts.UpdatedAt,
+	).SET(
+		postgres.String(displayName), postgres.Bool(true),
+		postgres.Bool(true), postgres.TimestampzT(time.Now().UTC()),
+	).WHERE(table.Accounts.AccountID.EQ(postgres.UUID(acc.ID))).
+		RETURNING(table.Accounts.AllColumns)
+
+	var row model.Accounts
+	if err := stmt.QueryContext(ctx, s.db, &row); err != nil {
+		return Account{}, fmt.Errorf("account: provision robot %q: %w", externalID, err)
+	}
+	return modelToAccount(row), nil
+}
+
 // ProvisionTelegram provisions (or finds) the account bound to a Telegram
 // identity. On first contact only, it seeds the new account's preferred language
 // from the Telegram client languageCode (when it maps to a supported language) and
-// its display name from firstName (falling back to username); an already-existing
+// its display name sanitized from firstName (falling back to username, then to a
+// generated placeholder when neither yields any letters); an already-existing
 // account is returned unchanged, so a later profile edit is never overwritten.
 func (s *Store) ProvisionTelegram(ctx context.Context, externalID, languageCode, username, firstName string) (Account, error) {
 	return s.provision(ctx, KindTelegram, externalID, telegramSeed(languageCode, username, firstName))
@@ -155,19 +185,21 @@ type provisionSeed struct {
 
 // telegramSeed derives the create-time seed from Telegram launch fields: a
 // supported preferred language from languageCode (an ISO-639 code, possibly
-// region-tagged like "ru-RU"), and a display name from firstName or, failing that,
-// username (capped to maxDisplayName runes).
+// region-tagged like "ru-RU"), and a display name sanitized from firstName or,
+// failing that, username (sanitizeDisplayName strips disallowed characters to the
+// editable format). When neither yields any letters, it falls back to a generated
+// placeholder in the seeded language (placeholderDisplayName).
 func telegramSeed(languageCode, username, firstName string) provisionSeed {
 	var seed provisionSeed
 	if lang, _, _ := strings.Cut(strings.ToLower(strings.TrimSpace(languageCode)), "-"); lang == "en" || lang == "ru" {
 		seed.preferredLanguage = lang
 	}
-	name := strings.TrimSpace(firstName)
+	name := sanitizeDisplayName(firstName)
 	if name == "" {
-		name = strings.TrimSpace(username)
+		name = sanitizeDisplayName(username)
 	}
-	if utf8.RuneCountInString(name) > maxDisplayName {
-		name = string([]rune(name)[:maxDisplayName])
+	if name == "" {
+		name = placeholderDisplayName(seed.preferredLanguage)
 	}
 	seed.displayName = name
 	return seed